Ka-52 Hokum B "Alligator"

Created by the Kamov Design Bureau, the unusual co-axial rotor configuration has in some small way become one of the company’s trademarks. Anti-armour helicopter design usually copies the Bell AH-1 Cobra configuration, tandem cockpit, single main rotor and anti-torque tail rotor.

Kamov’s design approach is tempered by the view that the typical tail-rotor configuration imposes an unnecessarily high-degree of vulnerability to ground fire. Also the long transmission shaft and associated gearbox places high-loads on the tail boom, a structure vulnerable to ground strikes and contact damage when hovering in confined spaces.

Eliminating the anti-torque rotor and associated gearbox transmission is achieved by adopting a twin rotor configuration. One rotor is mounted above the other and spin in opposite directions thus cancelling the effect of torque. This system makes ground maintenance easier and more importantly to a pilot - increases helicopter performance, nearly all the power provided by the two turboshaft engines is delivered straight to the main rotor. There is no need to use power driving a tail rotor that doesn’t provide any lift. Increased power allows for heavier armament more armour protection and greater speed – all of these are fundamental constraints when designing a battlefield helicopter.

The co-axial rotor configuration of the Ka-52 has other benefits; the helicopter is capable of performing flat-turns throughout the entire flight speed range. This affords an ability to rapidly turn the nose onto a target even at dash speeds or rapid sideways transitioning to evade fire while attacking. Mechanics are battle-hardened, systems have been proved against rounds up to 23mm, the power-plant can run for 30 minutes without oil, this gives the pilot an opportunity to land in a safe location in the event the oil system is damaged.

The Alligator is a high-performance all-weather, day and night attack helicopter. The primary mission role being similar to the Comanche - battlefield reconnaissance and strike co-ordination. To achieve this, there is an impressive avionic and sensor fit.

First is the FH-01 Arbalat (Crossbow) centimetric and millimetric wavelength radar made by Phazotron. The centimetric antenna of the Crossbow has a 360-degree search capability and mounted in a small 2-foot diameter dome on top of the rotor mast. This provides the Ka-52’s air search and track capability. The larger millimetric wave antenna mounted in the nose of the helicopter is used to detect ground objects (such as vehicles) and provide information for 3D terrain mapping avionics. Little is known about the search parameters of the Crossbow, estimates place it’s ground search and track capability in excess of 11km.

The helicopters electro-optical package consists of a number of systems. Like the American AH-64 and RAH-66 combat helicopters, there are two discreet night vision sensors, one for the pilot and another for weapon sighting. A sensor ball positioned on the roof between the cockpit and the rotor mast houses the Samshit (Boxwood) STS gyro-stabilized reconnaissance & sighting unit. The Samshit incorporates a FLIR imager (PNVS), which feeds the pilots’ helmet-mounted display. Located under the fuselage is a small hemispherical fairing which houses the weapon operators’ periscope: its rotation and elevation is aligned with the Samshit pod. Laser designation and LLLTV (Low Light Level Television) weapon guidance is achieved using a standard Shkval-V turret; this flat windowed chin mounted housing is used for employing most of the Ka-52’s beam riding weapons such as the supersonic Vikhr (Whirlwind). The accuracy of the target guidance system is so great, it is said you can choose which "wheel" to hit on targets as far as 8 to 10km away. Because of this accuracy the Vikhr can be used against air-to-ground or air-to-air targets, the missile adjusts its profile accordingly.

The "Glass Cockpit" is a new feature in Kamov helicopters, four French made multi-function colour displays provide most of the instrumentation and systems management required for flight operations. An advanced EWS (Electronic Warfare Suite) provides early warning and countermeasures; basic components are the RWR (Radar Warning Receiver), Missile Warning System (MWS), Laser Warning Receiver (LWR) and chaff / flare launchers. The EWS displays threat information on a moving map display allowing the crew to relate threat bearing and distance to their immediate surroundings. Together with information from the radar and electro-optical sensors, this target data is automatically exchanged via a digital communications system to other force elements.

Navigation utilizes a combination of Inertial Guidance (laser gyroscopes and accelerometers) and GPS signals from both GLOSNASS and NAVSTAR satellites. This positional information is fed to an electronic moving map display that can be called up on one of the MFDs and also transmitted digitally to a ground command centre. Radio outfitting is made up of three VHF transceivers; one for monitoring the "guard" channel, one for secure communications and another for communicating with other mission specific force elements.

Gun installation consists of a 30mm 2A32 cannon mounted on a hydraulic drive that allows a limited amount of deflection: -2° to +9° azimuth (side to side) and +3° to -37° elevation (up and down). Cannon ammunition is supplied from two cartridge boxes, the fore box contains 240 rounds of armor piercing tracers, and the rear box contains 230 high-explosive incendiary rounds. The pilot selects which kind of ammunition to feed the gun and chooses between two rates of fire: high (550-600 rounds per minute) or low (350 rounds per minute). Burst lengths are automatically adjusted to either 10 or 20 rounds according to the rate of fire.

Kamov has gone to considerable lengths for crew protection. Just as with the Comanche, the crew cockpit is slightly pressurized to prevent NBC contamination. Protecting the crew from ground fire is approximately 300kg (661 lbs.) of steel hybrid armor in two layers. The steel armor is proved against direct hits by 20mm rounds. Lighter ceramic armor was rejected due to its tendency to shatter after successive impacts. In an emergency landing, the fuselage and landing gear struts can crumple to absorb large impact forces. Cockpit components and other structural elements are designed to preclude crew compartment volume compression by no more than 10-15%.

Another unusual feature of this helicopter is the "Pilot Rescue" capability by way of the K-37-800 ejection seat which was first fitted to the Ka-50 (the first helicopter in the world to be fitted with an ejector seat). Once the ejection handle has been pulled, a very carefully timed series of events take place. First, explosive charges in the rotor blade roots are detonated resulting in the separation of all 6 blades (this is potentially dangerous for any nearby onlookers). Both cockpit canopies are ejected sideways then the towing rocket on both ejection seats fire in low-thrust mode. When the towing-line is pulled taught the rocket increases thrust pulling the seat up on its mounting rails and out of the helicopter. After the rocket burn, the seat falls away and a cute is deployed. This ejection can be performed throughout the entire flight envelope including inverted flight (given a minimum altitude of 90 meters). Should a pilot eject over water, the seat is also fitted with survival pack and life raft. A survival beacon is activated automatically on ejection.

The Ka-52 is simple to control, highly maneuverable and has a lethal day/night weapons capability. A valuable asset for any modern army.

Development History

Since the mid-1970’s, the mainstay of the soviet attack helicopter fleet was the Mi-24 Hind. This rather large and heavy helicopter, originally built as a flying Infantry Fighting Vehicle (IFV), has a capacity for ferrying up to 8 fully equipped soldiers. Over the years, it was realised that this troop carrying capability was underused; smaller lightweight (and more manoeuvrable) helicopters proved more suited to the anti-armour role. The USSR government took the decision to initiate the development of the next generation of army helicopters in December 1976. The task was handed to the Kamov Design Bureau and the Mil Helicopter Plant of Moscow.

In the early 1980’s, Kamov demonstrated its light attack helicopter concept, it was designated V-80 (for "Helicopter of the 80s", V = "vertolyot" meaning helicopter). This helicopter was later re-designated the Ka-50 Hokum. In June 1982, the first Ka-50 prototype designated "White 010" made its maiden flight.

By 1990, soviet Army Aviation (Armeiskaya Aviatsiya) published its requirement for an anti-tank helicopter with night fighting capability. The Mil Helicopter Plant of Moscow submitted its two-seat Mi-28 Havoc and Kamov demonstrated their single-seat Ka-50 Hokum. Both officially won tender in 1994 and a year later, President Yeltsin signed a decree commissioning the Ka-50 for military service.

The first airframe left its Siberian factory in 1992. However lack of money forced production to stop after only 12 airframes had been built, and most of those did not meet the night flying requirement. As a result, Mil continued development of the Havoc, giving the company a chance to develop better night flying technologies and offer a more attractive helicopter.

With the difficulty in manufacturing heat vision equipment at that time, emphasis was placed on radar development. The Mi-28 and Ka-50 used the prototype Almaz and Arbalat (Crossbow) radar systems respectively. Advances in radar and FLIR design resulted in a much more complex avionic suite in both helicopters. This proved to be a great disadvantage in the single-seat Ka-50 where the pilot workload was considerably greater. Given the high weight of Soviet avionics, fitting a comprehensive suite of avionic systems to a two-seat helicopter was deemed impractical.

As it happens, a two-seat version of the Ka-50 had been constructed, used for pilot training it featured a side-by-side cockpit configuration. By adding more powerful engines and reducing protective armour, a practical two-seat attack helicopter was demonstrated. Further to this, Kamov contracted western companies to supply lighter and user-friendlier avionic components.

The first Ka-52 prototype designated "White 061" was premiered at the "Bangalore Aero India" show in 1996. It was based on the 11^th production Ka-50 with a rebuilt front-fuselage section. It is estimated the Ka-52 is around 80-85 percent identical to the basic Ka-50 helicopter airframe and main system components. The principal dimensions of both helicopters remain more or less the same. White 061 was flown for the first time on the 25^th June 1997 at Kamov’s flight test base in Lyubertsty.

Experience with the Mi-24 Hind in Afghanistan had convinced Kamov that better crew co-ordination could be achieved by crew members sitting next to each other. Although interestingly Mil was not so convinced, and neither was Turkey when it evaluated the Hokum in 1998. Consequently this marked the start of an unlikely east/west relationship; Kamov in collaboration with Israeli Aircraft Industries (IAI) began work on the Ka-50-2. This is an export variant of the Ka-50/52 but has options for a traditional tandem cockpit and a turreted 20mm cannon mounted under the belly. The IAI sensor fit includes a night targeting and laser range-finder/designator package compatible with a subset of western missile systems.

Kamov are currently offering Armeiskaya Aviatsiya a mixed package of Ka-52s with existing Ka-50s upgraded to an all weather/night attack capability. Together they will adopt roles of battlefield reconnaissance, target identification/distribution and hand-off in a similar fashion to the AH-64D Apache and AH-64D fitted with the Longbow radar/fire control system.

Specifications

Armament

• 2A42 30mm cannon*
• S-8 80mm rocket*
• S-13 122mm rocket*
• Vikhr-M (AT-9) laser guided air-to-surface*
• Igla-V air-to-air missile*
• Kh-25ML (AS-12 Kegler) laser guided air-to-surface
• Kh-25MP anti-radar missile
• R-73 (AA-11 Archer) air-to-air missile
• KMGU-2 submunitions dispenser
• UPK-23 gun pod twin 23mm*
• 500-kg aerial bomb
• 250-kg aerial bomb

* Featured in Comanche Hokum

Features

• Co-axial rotor configuration
• Zvezda K-37-800 pilot ejection system
• Phazotron FH-01 Arbalat (Crossbow) CMW/MMW radar
• Shkval-V gyro-stabilized recon unit with TV, FLIR and Laser
• Under hull turret-mounted periscope
• Target data exchange over digital communications
• Automatic flight-control system
• Glass cockpit with multi-function colour displays
• Hands On Collective And Stick (HOCAS)
• Helmet Mounted Display
• High power-to-weight ratio
• Reduced pilot workload